An intravenous pyelogram is performed by injecting iodinated
contrast material into a vein. As the contrast is excreted by the
kidney, x-rays are obtained. An IVP is a useful test to determine
both anatomy and function. It provides high resolution images so that
the renal pelvis, calyces and ureter are all well seen. One can
detect absence of function or perfusion to a kidney when no contrast
is excreted.

Usefullness. An IVP is useful in patients with hematuria,
hydronephrosis, or abdominal pain thought to be related to the
kidneys.

Limitations: An IVP is an invasive test. It requires placement of
an intravenous line. Because significant renal function is required
to concentrate and excrete the contrast material, IVP's are not
useful in patients with renal dysfunction. Newborns rarely have
sufficient renal concentrating ability to allow the kidneys to be
seen on an x-ray. An IVP will detect renal function, but it is not
very sensitive in comparing the function of two kidneys. Nuclear
renograms are the best G/U imaging study to measure renal function.

Indications: An IVP may be useful in evaluating children with
urine infections, suspected kidney stones, hematuria, or urinary
tract obstruction. If you suspect a renal tumor an ultrasound would
be a better study.